The present invention relates to image forming devices, imaging assemblies, sensors, and methods of forming an image.
Electrophotographic processes for forming images upon media are well known in the art. Typically, these processes include an initial step of charging a photoreceptor which may be provided in the form of a drum or continuous belt having photoconductive material. Thereafter, an electrostatic latent image may be produced by exposing the charged area of the photoreceptor to a light image using a light-emitting diode array, or scanning the charged area with a laser beam in exemplary configurations.
Particles of toner may be applied to the photoreceptor upon which the electrostatic latent image is disposed such that the toner particles are transferred to the electrostatic latent image. Thereafter, a transfer step occurs wherein the toner particles are transferred from the photoreceptor to the media while maintaining the shape of the image formed upon the photoreceptor. A fusing step is utilized to fix the toner particles in the shape of the image to the media. A subsequent step can include cleaning or restoring the photoreceptor for a next printing cycle.
Two operational parameters greatly affect the final print quality of the toner image supplied to the media. For example, the electric field in the transfer nip of an electrophotographic printing device and an effective temperature in the fuser nip are vital to ensure optimized image quality and achievable print. Two variables in printing media that affect the electric fields in the transfer nip and the effective temperature in the fuser nip are basis weight and water content. These two variables manifest themselves as differences in dielectric thickness, heat capacity and thermal conductivity for a given media in an environment.
Referring to toner transfer operations, toner transfer electric fields are largely dependent upon the capacitance of the media. Most transfer systems of conventional electrophotographic devices use constant supply voltages that are applied to respective conductive transfer rollers. Typically, the applied voltages are set relatively high to accommodate thicker (i.e., lower capacitance) media. Unfortunately, this condition can result in less than optimum electric fields for thinner (i.e., higher capacitance) media. In some conventional arrangements, a user can manually adjust fuser temperatures using a control panel or software. Typically, such adjustments are made after problems in fusing quality are noticed.
The above conventional image forming system configurations have associated drawbacks of requiring knowledge of the user to implement transfer and fusing adjustments as well as knowledge of the proper adjustment to improve transfer and fusing quality. Therefore, a need exists to provide image forming devices and methods which provide improved print quality for different types of media.
The present invention includes image forming devices, imaging assemblies, sensors, and methods of forming an image. One aspect of the present invention provides an image forming device comprising: a housing configured to guide media along a media path; an input device configured to receive an image; a sensor adjacent the media path and configured to monitor the media and to generated signal responsive to the monitoring: and an imager adjacent the media path and configured to provide developing material corresponding to the image upon the media according to an imaging parameter and to adjust the imaging parameter responsive to the signal.
A second aspect of the invention provides an imaging assembly of an image forming device comprising: a sensor configured to monitor media traveling along a media path of an image forming device and to generate a signal responsive to the monitoring; a controller coupled with the sensor and configured to receive the signal and to adjust an imaging parameter responsive to the signal; and an imager adjacent the media path and coupled with the controller and configured to provide developing material upon the media according to the imaging parameter.
According to another aspect, the invention provides a sensor configured to monitor media comprising: a first electrode positioned adjacent a first surface of media to be monitored; a second electrode positioned adjacent a second surface of the media; and wherein the first electrode and second electrode are substantially aligned to form a capacitor, and the media provides a dielectric material intermediate the first electrode and the second electrode.
Another aspect of the present invention includes a method of forming an image upon media comprising: providing an image forming device; providing an image; transferring developing material corresponding to the image to media according to an imaging parameter; monitoring the media; and adjusting the imaging parameter responsive to the monitoring.
Other features and advantages of the invention will become apparent to those of ordinary skill in the art upon review of the following detailed description, claims, and drawings.